Why's everything a "div"?

Hi! I’m new here (sub and HTML).

I’m trying to boost my startup by making an online store, but I don’t know how to, and at the moment I can’t invest enough money to pay someone to do it for me. So, I’ve been trying to learn how to do it by myself, watching some YouTube videos and reading about HTML5 and CSS3, but I haven’t found any free courses to learn from (in Spanish)

I’m using Mimo (Duolingo for programming), but their system is pay-to-learn, and it would take months to learn the basics there. So, I would like to know if there are any free courses to learn how to build an online store using both HTML5 and CSS3.

I’ve tried watching FalconMasters and CódigoFacilito on YouTube, but both focus only on HTML.

Thanks in advance!

https://preview.redd.it/v0j3xgpe0hmd1.png?width=1800&format=png&auto=webp&s=a4fefd8a8a8f7a8d5173cc3e197b8e6bfcda84f3

how does it work it:

it loads a low-res image first from the img src then in the hr-src atrbute it loads the high-res image in the background the once loaded replaces the low-res url with the high-res one.

Check out the repo a star would be Awesome

Demo